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1.
Int J Biol Macromol ; 264(Pt 1): 130600, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38442829

ABSTRACT

We explored the rheological and tribological properties of potato starch agglomerated with a sugar binder (maltodextrin or lactose) at various concentrations by using a fluidized bed granulator. The magnitudes of consistency index and apparent viscosity of agglomerated potato starch (APS) decreased as the binder concentration was increased. Moreover, APS with a sugar binder showed lower viscoelastic moduli and higher tan δ values compared to APS with water as the binder (the control). The gel strength of all agglomerates decreased as the sugar concentration was increased. All samples showed anti-thixotropic behavior, and especially, APS with 20 % lactose showed a small anti-thixotropic area. Utilizing the Arrhenius equation clearly elucidated the effect of temperature on the apparent viscosity of all the samples. Although the maltodextrin concentration had little influence on the activation energy of APS, it increased as the lactose concentration was increased. APS samples with a sugar binder showed greater friction coefficient values compared to the control, with maltodextrin having a significant impact. The findings indicate that the rheological and tribological properties of APS rely on the type and concentration of sugar binder.


Subject(s)
Solanum tuberosum , Lactose , Starch , Sugars , Temperature , Rheology , Viscosity
2.
AJNR Am J Neuroradiol ; 45(5): 562-567, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38290738

ABSTRACT

BACKGROUND AND PURPOSE: The DWI-FLAIR mismatch is used to determine thrombolytic eligibility in patients with acute ischemic stroke when the time since stroke onset is unknown. Commercial software packages have been developed for automated DWI-FLAIR classification. We aimed to use e-Stroke software for automated classification of the DWI-FLAIR mismatch in a cohort of patients with acute ischemic stroke and in a comparative analysis with 2 expert neuroradiologists. MATERIALS AND METHODS: In this retrospective study, patients with acute ischemic stroke who had MR imaging and known time since stroke onset were included. The DWI-FLAIR mismatch was evaluated by 2 neuroradiologists blinded to the time since stroke onset and automatically by the e-Stroke software. After 4 weeks, the neuroradiologists re-evaluated the MR images, this time equipped with automated predicted e-Stroke results as a computer-assisted tool. Diagnostic performances of e-Stroke software and the neuroradiologists were evaluated for prediction of DWI-FLAIR mismatch status. RESULTS: A total of 157 patients met the inclusion criteria. A total of 82 patients (52%) had a time since stroke onset of ≤4.5 hours. By means of consensus reads, 81 patients (51.5%) had a DWI-FLAIR mismatch. The diagnostic accuracy (area under the curve/sensitivity/specificity) of e-Stroke software for the determination of the DWI-FLAIR mismatch was 0.72/90.0/53.9. The diagnostic accuracy (area under the curve/sensitivity/specificity) for neuroradiologists 1 and 2 was 0.76/69.1/84.2 and 0.82/91.4/73.7, respectively; both significantly (P < .05) improved to 0.83/79.0/86.8 and 0.89/92.6/85.5, respectively, following the use of e-Stroke predictions as a computer-assisted tool. The interrater agreement (κ) for determination of DWI-FLAIR status was improved from 0.49 to 0.57 following the use of the computer-assisted tool. CONCLUSIONS: This automated quantitative approach for DWI-FLAIR mismatch provides results comparable with those of human experts and can improve the diagnostic accuracies of expert neuroradiologists in the determination of DWI-FLAIR status.


Subject(s)
Diffusion Magnetic Resonance Imaging , Ischemic Stroke , Humans , Male , Female , Ischemic Stroke/diagnostic imaging , Aged , Retrospective Studies , Diffusion Magnetic Resonance Imaging/methods , Middle Aged , Software , Aged, 80 and over , Sensitivity and Specificity , Image Interpretation, Computer-Assisted/methods , Reproducibility of Results
3.
Int J Biol Macromol ; 253(Pt 2): 126559, 2023 Dec 31.
Article in English | MEDLINE | ID: mdl-37657581

ABSTRACT

Our goal was to investigate the effects of various conditions of media (NaCl, sucrose, pH, and temperature) on the steady and dynamic shear rheological properties of a concentrated ternary gum mixture system (1.0 wt%) containing xanthan gum (XG), guar gum (GG), and carboxymethyl cellulose (CMC). Regardless of the media conditions, all gum mixtures exhibited a high shear-thinning behavior with a low flow behavior index (<0.30). NaCl addition resulted in a decrease in the consistency index (K, 32.8-16.1 Pa·sn) and apparent viscosity at 50 s-1 (ηa,50, 1.00-0.75 Pa·s), as well as the elastic modulus (G') and viscous modulus (G″) due to the charge screening effect. Similar result was observed with an increase in acidity of media. The presence of sucrose also induced the decrease in the ηa,50, K, G', and G″ values of the ternary gum, but tan δ (G″/G') decreased, indicative of higher weak gel-like properties. No effect of NaCl or sucrose addition on the temperature dependence of G' values was observed, whereas pH adjustment was impacted. These results demonstrated that the presence of co-solute, the acidity of media, and temperature influenced the rheological properties of ternary gum, and in particular acid condition gave a great impact.


Subject(s)
Carboxymethylcellulose Sodium , Sodium Chloride , Temperature , Sucrose , Polysaccharides, Bacterial/chemistry , Plant Gums/chemistry , Hydrogen-Ion Concentration , Rheology , Viscosity
4.
Int J Biol Macromol ; 181: 232-240, 2021 Jun 30.
Article in English | MEDLINE | ID: mdl-33775758

ABSTRACT

Understanding the agglomeration of cellulose derivatives is crucial for the production of instant gum-based food thickeners. In the present study, physical, rheological, and structural properties of agglomerated water-soluble cellulose gums (CGs), such as carboxymethylcellulose (CMC), hydroxypropylmethylcellulose (HPMC), and methylcellulose (MC), were investigated at different concentrations of maltodextrin (MD) as a binder for fluidized-bed agglomeration. Among the CG agglomerates in the presence of MD, CMC exhibited better flowability and lower cohesiveness, showing lower Carr index and Hausner ratio values. The MC agglomerates with 20% MD exhibited higher porosity than the other CGs due to the size enlargement of MC particles, which was confirmed via scanning electron microscopy images and size distribution profiles. The dynamic moduli of the CG agglomerates were significantly decreased by the addition of MD and also decreased with increasing MD concentration. The tan δ values of the agglomerates increased with increasing MD concentration, indicating the enhancement of their viscous properties. These results suggest that the physical, rheological, and structural properties of cellulose derivatives with different types of CG can be greatly influenced by their agglomerate growths during fluidized-bed agglomeration of particles with the different concentrations of MD binder.


Subject(s)
Cellulose/chemistry , Rheology , Cellulose/ultrastructure , Elastic Modulus , Particle Size , Polysaccharides/chemistry , Porosity , Stress, Mechanical
6.
Lupus ; 29(1): 52-57, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31793379

ABSTRACT

BACKGROUND: Reduced renal function is associated with worse renal outcome in patients with lupus nephritis (LN). However, there is insufficient knowledge regarding renal function recovery in patients with LN with reduced baseline renal function. Therefore, the present study aimed to investigate renal function recovery and related factors in patients with reduced baseline renal function. METHODS: The present retrospective longitudinal cohort study included patients with LN and reduced renal function. Reduced renal function was defined as an estimated glomerular filtration rate (eGFR) of <60 mL/min/1.73 m2. Recovery of renal function was determined by an eGFR of >60 mL/min/1.73 m2 at six months after baseline, and factors associated with it were evaluated using logistic regression analysis. RESULTS: We included 90 patients with LN, with a mean eGFR value of 37.2 ± 13.9 mL/min/1.73 m2. Forty-six (51.1%) patients recovered their renal function after six months. On multivariate analysis, hydroxychloroquine use (odds ratio (OR) = 3.891, 95% confidence interval (CI) 1.196-12.653, p = 0.024), prolonged LN (OR = 0.926, 95% CI 0.874-0.981, p = 0.009) and high-grade tubular atrophy (OR = 0.451, 95% CI 0.208-0.829, p = 0.013) were associated with renal function recovery. During follow up, 25 patients were on end-stage renal disease (ESRD). Kaplan-Meier analysis revealed that renal function recovery after six months and lower probability of ESRD are associated. CONCLUSIONS: In patients with LN and reduced renal function, renal function recovery at six months was associated with use of hydroxychloroquine and inversely related to longer duration of LN and higher grade of tubular atrophy.


Subject(s)
Antirheumatic Agents/therapeutic use , Glomerular Filtration Rate/drug effects , Hydroxychloroquine/therapeutic use , Lupus Nephritis/drug therapy , Adult , Antirheumatic Agents/pharmacology , Female , Humans , Hydroxychloroquine/pharmacology , Longitudinal Studies , Lupus Nephritis/physiopathology , Male , Middle Aged , Recovery of Function/drug effects , Retrospective Studies
7.
Int J Tuberc Lung Dis ; 23(11): 1228-1234, 2019 11 01.
Article in English | MEDLINE | ID: mdl-31718761

ABSTRACT

OBJECTIVE: To examine the relationship between high-sensitivity C-reactive protein (hs-CRP) levels and lung function in a community-based cohort of South Korea.DESIGN: The Ansung-Ansan cohort database (an ongoing prospective study of a community-based population) was used in the analysis. We defined airway obstruction as the ratio between forced expiratory volume in 1 sec:forced vital capacity ratio (FEV1:FVC) of <95% of the predicted value for a healthy person. We also used the serum level of hs-CRP as a marker of inflammation. Multivariate analysis was performed with adjustment for the clinical characteristics of the participants.RESULTS: A total of 5528 individuals were eligible for the study. The average age was 55.1 years, and 47.8% were males. The prevalence of airway obstruction was 9.0%, and the mean hs-CRP level was 1.51 mg/dl. Serum hs-CRP levels increased with the severity of airway obstruction, and the latter worsened with an increase in the hs-CRP level. In multivariate analysis, as the hs-CRP level increased, FEV1 and FVC decreased. A higher FEV1:FVC ratio was associated with lower hs-CRP levels in males.CONCLUSION: Higher hs-CRP levels were associated with decreased FEV1 and FVC in a general population of Korea. The FEV1:FVC ratio decreased with an increase in the hs-CRP level in males.


Subject(s)
Airway Obstruction/epidemiology , C-Reactive Protein/analysis , Lung/physiopathology , Pulmonary Disease, Chronic Obstructive/epidemiology , Airway Obstruction/blood , Airway Obstruction/physiopathology , Biomarkers/blood , Female , Forced Expiratory Volume , Humans , Linear Models , Male , Middle Aged , Multivariate Analysis , Predictive Value of Tests , Prospective Studies , Pulmonary Disease, Chronic Obstructive/blood , Pulmonary Disease, Chronic Obstructive/physiopathology , Republic of Korea/epidemiology , Severity of Illness Index , Spirometry , Vital Capacity
8.
Lupus ; 28(11): 1294-1301, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31583978

ABSTRACT

OBJECTIVES: Favourable long-term prognosis in proliferative lupus nephritis (LN) is associated with the achievement of complete renal response (CR), which is defined as a urine protein/creatinine ratio (UPCR) of < 0.5. However, it is unclear whether a more stringent cut-off for proteinuria (normal value of proteinuria; UPCR < 0.15) is better than CR. We aimed to evaluate the effect of stringent CR, defined as a UPCR of <0.15, on long-term renal outcomes in proliferative LN. METHODS: We included 87 patients with class III or IV LN who achieved CR at one year after induction therapy. Clinical and laboratory data were compared between the stringent and non-stringent CR groups. Logistic regression analysis was performed to identify factors associated with achievement of stringent CR. Cox analysis was performed to analyse the risk factors for renal flare and development of chronic kidney disease (CKD). RESULTS: The stringent and non-stringent CR groups included 58 and 29 patients, respectively. The two groups showed no significant baseline differences in terms of the clinical, laboratory and pathological classification. The sustained CR rates during five years were 91.3% and 50.0% (p = 0.014) in the stringent and non-stringent CR groups, respectively. In Cox analyses, the achievement of stringent CR was associated with a lower risk of five-year renal flare rate (hazard ratio (HR) = 0.161, 95% confidence interval (CI) 0.063-0.411, p < 0.01) and development of CKD (HR = 0.189, 95% CI 0.047-0.752, p = 0.018). Mycophenolate mofetil induction therapy was associated with achievement of stringent CR at a borderline level of significance (HR = 7.268, 95% CI 0.894-59.089, p = 0.064). CONCLUSION: Achievement of stringent CR predicted lower risk of renal flare and development of CKD in proliferative LN. These findings suggest that stringent CR is a valuable treatment target in proliferative LN.


Subject(s)
Immunosuppressive Agents/administration & dosage , Lupus Nephritis/physiopathology , Mycophenolic Acid/administration & dosage , Proteinuria/epidemiology , Adult , Female , Humans , Lupus Nephritis/drug therapy , Male , Middle Aged , Prognosis , Proteinuria/etiology , Remission Induction , Retrospective Studies , Risk Factors , Treatment Outcome , Young Adult
10.
Diabet Med ; 36(10): 1312-1318, 2019 10.
Article in English | MEDLINE | ID: mdl-31254366

ABSTRACT

AIM: Few data are available on the gender-related differences in the prognostic impact of diabetes in people with heart failure. This study was performed to investigate whether there is a gender difference in the association between diabetes and long-term clinical outcomes in people hospitalized for heart failure. METHODS: A total of 3162 people hospitalized with heart failure (aged 67.4 ± 14.1 years, 50.4% females) from the data set of the nationwide registry were analysed. The primary endpoint was a composite of all-cause mortality and heart failure readmission. RESULTS: People with diabetes (30.5% for males vs. 31.1% for females, P = 0.740) were older and had more unfavourable risk factors and laboratory findings than those without diabetes in both genders. During a median follow-up period of 549 days, there were 1418 cases of composite events (44.8%). In univariable analysis, the coexistence of diabetes was significantly associated with a higher incidence of composite events in both genders (P < 0.05 each for males and females). In multivariable analysis, the prognostic impact of diabetes on the development of composite events remained significant in females even after controlling for potential confounders (hazard ratio 1.43, 95% confidence intervals 1.12-1.84; P = 0.004). However, an independent association between diabetes and composite events was not seen in males in the same multivariable analysis (P > 0.05). CONCLUSIONS: In people with heart failure, the impact of diabetes on long-term mortality and heart failure readmission seems to be stronger in females than in males. More careful and intensive management is needed especially in females with heart failure and diabetes.


Subject(s)
Diabetes Mellitus/epidemiology , Heart Failure/epidemiology , Sex Factors , Aged , Aged, 80 and over , Comorbidity , Diabetes Mellitus/mortality , Female , Heart Failure/mortality , Hospitalization , Humans , Male , Middle Aged , Patient Readmission , Prognosis , Registries , Republic of Korea/epidemiology , Risk Factors
11.
Bone Joint J ; 101-B(3): 260-265, 2019 03.
Article in English | MEDLINE | ID: mdl-30813788

ABSTRACT

AIMS: The aim of this study was to evaluate the clinical and radiological outcomes of locking plate fixation, with and without an associated fibular strut allograft, for the treatment of displaced proximal humeral fractures in elderly osteoporotic patients. PATIENTS AND METHODS: We undertook a retrospective comparison of two methods of fixation, using a locking plate without an associated fibular strut allograft (LP group) and with a fibular allograft (FA group) for the treatment of these fractures. The outcome was assessed for 52 patients in the LP group and 45 in the FA group, with a mean age of 74.3 years (52 to 89), at a mean follow-up of 14.2 months (12 to 19). The clinical results were evaluated using a visual analogue scale (VAS) score for pain, the Constant score, the American Shoulder and Elbow Surgeons (ASES) score, and the range of movement. Radiological results were evaluated using the neck-shaft angle (NSA) and humeral head height (HHH). RESULTS: The mean forward elevation in the LP and FA groups was 125.3° (sd 21.4) and 148.9° (sd 19.8), respectively (p = 0.042), while other clinical factors showed no statistically significant differences between the groups. The changes in NSA and HHH immediately after the operation and at final follow-up were significantly better in the FA group than in the LP group (p = 0.015 and p = 0.021, respectively). CONCLUSION: For comminuted proximal humeral fractures in osteoporotic patients, locking plate fixation with a fibular strut allograft shows satisfactory short-term results with respect to humeral head support and maintenance of reduction, and may reduce the incidence of complications associated with fixation using a locking plate alone. Cite this article: Bone Joint J 2019;101-B:260-265.


Subject(s)
Fracture Fixation, Internal/methods , Fractures, Comminuted/surgery , Osteoporotic Fractures/surgery , Shoulder Fractures/surgery , Aged , Aged, 80 and over , Allografts , Bone Plates , Female , Fibula/transplantation , Fracture Fixation, Internal/adverse effects , Fracture Fixation, Internal/instrumentation , Humans , Male , Middle Aged , Retrospective Studies , Transplantation, Homologous
13.
Int J Biol Macromol ; 121: 424-428, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30321634

ABSTRACT

Physical and rheological properties of agglomerated xanthan gum (XG), commonly used as a food thickener for the management of the patients with dysphagia (swallowing difficulty), were investigated at different concentrations (0, 2, 4, and 6% w/w) of hydroxypropyl methylcellulose (HPMC) as a binder in the fluidized bed agglomeration process. Flow characteristics of agglomerated XG powder were evaluated using Carr index (CI) and Hausner ratio (HR). The agglomerated XG powders obtained by HPMC binder exhibited a better flowability and higher porosity than the agglomerated powder without binder due to the size enlargement of XG powder. Dynamic moduli (G' and G") of agglomerated XG powders at 2% and 4% HPMC were significantly higher than those of other powders. The tan δ values of agglomerated powders with HPMC binder were much lower than that of an agglomerated powder without HPMC, indicating that their elastic properties were enhanced because of the addition of HPMC binder. Results suggest that the use of HPMC in agglomeration process could considerably enhance the flow characteristics and rheological properties of XG powder.


Subject(s)
Hypromellose Derivatives/chemistry , Polysaccharides, Bacterial/chemistry , Rheology , Porosity
14.
Rev Sci Instrum ; 89(9): 094701, 2018 Sep.
Article in English | MEDLINE | ID: mdl-30278739

ABSTRACT

This study presents the investigation of superconducting joints fabricated using multifilament magnesium diboride (MgB2) wires for the development of persistent-current mode magnetic resonance imaging (MRI) magnets. The critical current of the jointed samples decreased with increasing cutting angle because the smaller cutting angle allowed greater exposure of the MgB2 filament, thereby increasing the contact area for the wire-bulk-wire connection. In addition, an appropriate pressing pressure (300 MPa) was necessary to establish the multifilament MgB2 joint without significant degradation of superconducting properties. The resistance of the optimal MgB2 joint, measured using the field-decay technique, was <1.5 × 10-14 Ω. Therefore, the proposed joint technique can be employed for developing multifilament MgB2 MRI magnets operating in the persistent-current mode.

15.
Science ; 360(6390): 795-800, 2018 05 18.
Article in English | MEDLINE | ID: mdl-29724905

ABSTRACT

The immune system responds vigorously to microbial infection while permitting lifelong colonization by the microbiome. Mechanisms that facilitate the establishment and stability of the gut microbiota remain poorly described. We found that a regulatory system in the prominent human commensal Bacteroides fragilis modulates its surface architecture to invite binding of immunoglobulin A (IgA) in mice. Specific immune recognition facilitated bacterial adherence to cultured intestinal epithelial cells and intimate association with the gut mucosal surface in vivo. The IgA response was required for B. fragilis (and other commensal species) to occupy a defined mucosal niche that mediates stable colonization of the gut through exclusion of exogenous competitors. Therefore, in addition to its role in pathogen clearance, we propose that IgA responses can be co-opted by the microbiome to engender robust host-microbial symbiosis.


Subject(s)
Bacteroides fragilis/immunology , Gastrointestinal Microbiome/immunology , Immunoglobulin A/immunology , Intestinal Mucosa/immunology , Intestinal Mucosa/microbiology , Animals , Bacterial Adhesion/immunology , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Bacteroides fragilis/genetics , Bacteroides fragilis/ultrastructure , Cells, Cultured , Humans , Mice , Polysaccharides, Bacterial/immunology , Symbiosis
16.
Int J Biol Macromol ; 115: 124-128, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29654858

ABSTRACT

The effect of CMC on the steady and dynamic shear rheological properties of binary mixtures of XG and GG was examined at different mixing ratios. All XG-GG-CMC ternary mixtures had high shear-thinning behavior and the n value of the sample with 5% CMC was the smallest compared with those of other samples. A marked increase in K and ηa,50 values was observed for ternary mixtures at a lower content (5%) of CMC, indicating that the synergistic interactions of the XG-GG binary mixture were affected by the content of CMC. The effect of temperature on the ηa,50 was well described by the Arrhenius equation for all samples. The activation energy values of all ternary gum mixtures are higher than that of binary gum mixture, and these values also decreased with an increase in CMC content from 5 to 15%. The dynamic moduli of ternary gum mixtures decreased with an increase in CMC content. The tan δ value of the ternary gum mixture with 5% CMC was much lower than those of other ternary mixtures. In general, these results suggest that the flow and dynamic shear rheological properties of XG-GG binary mixtures are strongly influenced by a small addition of CMC.


Subject(s)
Cellulase/chemistry , Galactans/chemistry , Mannans/chemistry , Plant Gums/chemistry , Polysaccharides, Bacterial/chemistry , Rheology , Shear Strength , Temperature
18.
Int J Biol Macromol ; 111: 77-81, 2018 May.
Article in English | MEDLINE | ID: mdl-29289667

ABSTRACT

The intrinsic viscosity ([η]) values of binary gum mixtures with xanthan gum (XG) and guar gum (GG) mixed with NaCl and sucrose at different concentrations as well as in the presence of different pH levels were examined in dilute solution as a function of XG/GG mixing ratio (100/0, 75/25, 50/50, and 0/100). Experimental values of concentration (C) and relative viscosity (ηrel) or specific viscosity (ηsp) of gums in dilute solution were fitted to five models to determine [η] values of binary gum mixtures including individual gums. A [η] model (ηrel=1+[η]C) of Tanglertpaibul and Rao is recommended as the best model to estimate [η] values for the binary gum mixtures with XG and GG as affected by NaCl, sucrose, and pH. Overall, the synergistic interaction of XG-GG mixtures in the presence of NaCl and sucrose showed a greatly positive variation between measured and calculated values of [η]. In contrast, the binary gum mixtures showed synergy only under an acidic condition (pH3). These results suggest that the NaCl and sucrose addition or acidic condition appears to affect the intermolecular interaction occurred between XG and GG at different gum mixing ratios.


Subject(s)
Galactans/chemistry , Mannans/chemistry , Plant Gums/chemistry , Polysaccharides, Bacterial/chemistry , Rheology , Viscosity , Hydrogen-Ion Concentration , Sodium Chloride/pharmacology , Sucrose/pharmacology
20.
RSC Adv ; 8(59): 34161, 2018 Sep 28.
Article in English | MEDLINE | ID: mdl-35548834

ABSTRACT

[This corrects the article DOI: 10.1039/C7RA01349C.].

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